By Edward Wong A terrorist group seeking an independent Muslim state in western China has released a video threatening an attack on the Olympic Games here, according to an American organization that tracks terrorist Internet posts.

In the lead-up to the Summer Olympics, the Chinese government has launched a security clampdown in Beijing unprecedented in the country [BusinessWeek.com, 07/28/08]. But in other parts of China, the security presence is not as intense, and on Aug. 4, terrorists took advantage.

By Andrew Jacobs Jake Hooker and Tang Xuemei contributed research. * Two men armed with knives and explosives ambushed a military police unit in China's majority-Muslim northwest region Monday morning, killing 16 officers and wounding 16 others before being arrested, according to the state media.

KASHGAR, China _ China said Monday that two assailants in a truck mowed down a group of jogging policemen, then tossed grenades and slashed gasping survivors with knives in an attack that left 16 officers dead in this restive Muslim region in the nation's far west.

An attack Monday at a border police station in northwest China's Muslim-majority Xinjiang region killed 16 policemen and injured 16 more, police said. The attack comes just days before the start of the Summer Olympics in Beijing.

Grenade attacks Monday on a border patrol police station in China's northwest Xinjiang region killed 16 policemen and injured 16 more. Two attackers driving a truck tossed two grenades causing an explosion at the station in Kashi, the state-run Xinhua news agency reported.

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